import { JsonObject } from 'type-fest';
/**
 * Simple map based cache implementation with TTL.
 */
export declare class Cache<T> {
    private readonly ttl?;
    private readonly storage;
    constructor(ttl?: number);
    get isEmpty(): boolean;
    get(key: string): T | undefined;
    set(key: string, value: T): void;
    delete(key: string): void;
}
export declare class NamespaceCache {
    private readonly ttl?;
    private readonly storage;
    constructor(ttl?: number);
    get(namespace: string, key: string): JsonObject | undefined;
    set(namespace: string, key: string, value: JsonObject): void;
    delete(namespace: string, key: string): void;
}